Tube winding machine with tension indicator



June 2, 1959 J. F. BARNES ETAL 2,883,826

TUBE WINDING MACHINE WITH TENSION INDICATOR 7 Filed March 19, 1956 8 mm ga mm I i7 VENTORSI m1 mm% TUBE WINDING MAC WITH TENSIGN INDICATOR James F. Barnes, Van Nuys, and John H. Bent, North Hollywood, Calif., assignors to Foil Process Corporation, Van Nuys, Calih, a corporation of California Application March 19, 1956, Serial No. 572,561

Claims. (Cl, 7 3-143) This invention relates to an improvement in machines for spirally winding and laminating strips of material in continuous tube-forming operations.

One of the main objects of the present invention is to provide a tube-winding machine in which the tension of the tube winding belt may be easily and accurately controlled. Another object is to provide a tube winding apparatus equipped with means for easily and effectively applying any selected belt pressure upon a tube winding mandrel, so that the tubular products produced by the apparatus are uniform in wall thickness, diameter and strength. A further object is to provide a tube winding machine having indicator means for registering the tension of the tube winding belt so that the machine may be easily adjusted to provide optimum belt pressure upon a mandrel throughout a tube winding operation.

The invention is shown in an illustrative embodiment in the accompanying drawings, in which- Figure l is a broken perspective view of a tube winding machine equipped with the belt tension control means of the present invention; Figure 2 is an end elevation of the winding machines carriage or bed with the tension control reel removed therefrom; and Figure 3 is a top plan view partly in section, and taken along lines 3-3 of Figure 2.

In spiral tube winding machines, it has been found that unless the tension of the tube winding belt is maintained Within a relatively narrow range or tolerance throughout any particular winding operation, considerable variation in the size and strength of the tubular product produced by the machine will result. Undesirable variations in belt tension may be caused by wear, deterioration or stretching of the belt, or by adjustments in the position of the belt with respect to the mandrel of the machine. Furthermore, tubes wound with too little or too great a pressure upon the mandrel often cause the material that is being wound to wrinkle and distort. Where the machine is adapted to spirally wind and laminate strips of metal foil, it is essential that opti mum belt tension be maintained throughout any given operating period.

In the past, proper belt tension adjustment of tube winding machines has been largely a matter of guesswork involving the judgment of a skilled operator. It has been well recognized in the art that several years of training are generally necessary before an operator is able to feel the proper belt tension. Other aspects of the training, such as judging the optimum speed of the machine and adjusting the webs are more mechanical, and may be learned in a relatively short period of time.

It is evident that even where a spiral tube winding machine is run by a skilled operator, belt pressures still may vary considerably according to variations in the sensitivity of the operators feel or touch. Moreover, since manual testing of belt tension is done while the machine is not in operation, changes in belt tension which occur while the machine is running are not likely to be noticed by an operator. It will be seen from the following deatent O 2,888,826 Patented June 2, 1959 "ice scription that the present invention not only reduces or eliminates trial-and-error adjustment of belt tension at the commencement of a tube winding operation, thereby saving expense in time, labor and materials, but it insures proper and uniform belt tension throughout the operating period of the machine.

Figure 1 shows a tube Winding machine having the customary stand or frame 10, having a fiat top surface 11 upon which a standard 12 is bolted or otherwise secured. The enlarged top portion 13 of standard 12 carlies a stationary cylindrical mandrel 14 which extends horizontally along the top surface of the frame, and at a uniformly spaced distance therefrom.

A belt carriage is pivotally mounted upon stand or base 10, and essentially comprises an elongated bed 15, cylinders or rollers 16 and 17, and cylinder support frames 18 and 19. As shown best in Figures 2 and 3, bed 15 has a generally U-shaped cross section defined by upstanding legs 20 and 21 and base 22. The horizontal bed is pivotally mounted upon stand 19 by means of slotted flanges 23 and bolts 24, and may be shifted into any selected position traversing the elongated stand by manual rotation of hand wheel 25. Preferably, the hand wheel is rotatably mounted upon bed 15, and cooperates with conventional worm gear structure (not shown) to pivot the entire'carriage whenever the wheel is rotated.

Vertical cylinders 16 and 17 are journaled in frames 18 and 19, respectively, and, as shown in Figure 1, are disposed on opposite sides of mandrel 14. These cylinders are geared to shaft 26, which in turn is operably connected to flywheel 27 by any suitable connecting means. Power means, such as an electric motor (not shown), may be coupled by a belt connector with flywheel 27 to drive the vertical cylinders of the belt carriage. An endless tube winding belt 28 is entrained about the cylinders, and has a portion thereof looped or twisted about mandrel 14. Since the aforementioned structure is entirely conventional and is Well known in the art, a more detailed description is believed unnecessary herein.

In Figure 1, it will be seen that upright cylinder frame 19 is securely mounted upon the carriage bed adjacent one end thereof by bolts 29. Unlike frame 19, cylinder frame 18 is longitudinally slidable along the legs 26 and 21 of the bed. The means for sliding frame 13 and for achieving and maintaining a desired tension in tube winding belt 28 will now be described.

Across the front end of U-shaped bed 15 is a generally rectangular front plate 30. The plate may be mounted upon the bed by threaded studs or bolts 31, or by other suitable securing means such as Welding. An opening 32 in the plate freely receives the end portion of a rotatable shaft 33 which extends longitudinally of the bed within the channel defined by the legs and base thereof. The central portion 34 of cylinder support frame 18 projects downwardly between the upstanding legs of the carriage bed, and is provided with a threaded bore 35 adapted to receive the threaded rear portion of shaft 33.

As shown best in Figure 3, front plate 30 projects laterally from leg 20 of the carriage bed, and carries a vertical hinge pin 36 adjacent its outermost end. The upper and lower ends of pin 36 are pivotally received by the rearwardly extending upper and lower hinge members 37 permanently secured to a hinge plate 38. The hinge plate, therefore, lies directly in front of the front plate 30, and is equipped with a central opening 39 in horizontal alignment with opening 32 and the axis of shaft 33. The front portion of plate 38 adjacent the central opening may be recessed to receive a pair of annular grooved inserts 40 and 40d of hardened steel or other suitable material. These two inserts have curved surfaces in contiguous relation, the curved surface of member 40a providing a seat for member 40 for permitting pivotal movement of the latter, as will be described shortly. Within opening 39 is a cylindrical plug 41 having a reduced portion 42 extending forwardly therefrom and adapted to carry a manual control wheel 43, as illustrated in Figure 1. Plug 41 is also provided with an intermediate shoulder portion 43a which secures a grooved annular bearing race 44 in complementary relation to the bearing race provided by movable insert member 40. A plurality of bearings 45 ride along the adjacent grooves of the two race members to reduce rotational friction between plug 41 and hinge plate 38.

In the view presented in Figure 3, it will be seen that the rear portion of plug 41 is recessed to receive the front end of the elongated shaft 33. The shaft and plug are securely fastened together by any appropriate means, such as by screw means 46. Consequently, wheel 43, plug 41 and shaft 33 may be rotated as an integral unit. As the shaft is rotated in a clockwise direction, the slidable cylinder frame 18 is moved outwardly or forwardly. Conversely, when the wheel and shaft are rotated in a counter-clockwise direction, the roller support structure is driven rearwardly toward mandrel 14 and toward the cylinder support structure at the opposite end of the carriage bed.

To the lower surface of base 22, adjacent the forward end of the carriage bed, is welded a rearwardly and laterally extending support plate 47. To reinforce plate 47 and to provide a rigid support for pressure or force responsive means, a pair of vertical plates 48 and 49 are welded upon the support plate. Plate or wall 49 is parallel to bed 15, and may be weldably secured to the front plate 30, as shown in Figure 3. Plate 48 may be similarly secured to wall 49 and lies along a vertical plane perpendicular to leg 21 of the bed to provide an abutment wall for the pressure responsive means.

The pressure responsive means is represented generally by the numeral 50, and comprises a flexible U-shaped bar having one of its legs firmly connected to the vertical wall or plate 48 by bolt 51. The other leg 52 of the bar is equipped with a cup 53 along the forward side thereof. A steel ball 54 is carried between cup 53 and a notched arm 55 provided by hinge plate 38 adjacent one end thereof. When hinge plate 38 is pivoted rearwardly, leg 52 is flexed so that indicator plunger 56 engages the inclined surface of plunger anvil 57. The force exerted upon the plunger is translated into a direct visual reading by pressure indicator means or gauge 58. Since the indicator gauge is entirely conventional in structure, a more complete description is believed unnecessary.

- It is to be noted that the distance between the center of contact arm 55 and the axis of shaft 33 is the same as the distance between the axis of that shaft and the vertical axis of binge pin 36. Consequently, the force directed against arm 52 will be one-half of the longitudinal force imposed upon shaft 33. To insure proper operation of the belt tension control mechanism, and to limit the outward or forward pivotal movement of hinge plate 38, a cap screw 59 may be mounted upon the front plate 30 so that it projects through an opening 60 in the hinge plate. The diameter of screw or stud 59 is less than the diameter of opening 60 to avoid frictional or sliding engagement between these members. However, when the hinge plate is swung forwardly into an open position, the front surface of that plate abuts the enlarged head of the stud. Further limitation upon the outward pivotal movement of the hinge plate and shaft 33 may be provided by a collar 61 which engages the inner or rear surface of plate 30 when the hinge plate is moved into an open position. The collar may comprise a separate member welded upon the shaft or, if desired, may be formed integrally therewith.

Operation It is believed apparent from the foregoing description that as the control wheel is rotated, the cylinder support structure 18 moves either forwardly or rearwardly along carriage bed 15. When frame 18 is moved toward the control wheel, the tension in belt 28 and the belt pressure upon mandrel 14 is increased. Conversely, when the cylinder frame is moved away from the control wheel, the belt tension and the force exerted by that belt upon the mandrel are reduced. Since shaft 33 is carried only by movable frame 13 and pivotal hinge plate 38, the force imposed by belt 28 upon the mandrel is translated from arm 55 of the hinge plate to the pressure responsive means 50, and is recorded by the pressure indicator gauge 58. It will be noted in Figure 1 that belt 28 makes only one loop or revolution about the mandrel. Therefore, when the width of the belt and diameter of the mandrel are known, the actual pressure exerted by the belt on the mandrel may be easily and quickly ascertained.

It is apparent that unless means are provided for preventing lateral displacement of the front end portion of shaft 33 when hinge plate 38 is pivoted, such displacement would destroy the accuracy of any reading obtained from pressure gauge 58. To prevent lateral displacement of the shaft when the hinge plate is moved, the plate is equipped with a self-aligning bearing member 40. When the hinge plate is pivoted either forwardly or rearwardly, the curved rear surface of mem ber 40 rides across the correspondingly curved surface of the adjacent member 4911 which is carried by the hinge plate, and accommodates the lateral movement of the hinge member Without translating that movement to the shaft. As a result, a high degree of accuracy in the measurement of belt tensions is achieved.

For the production of spirally wound laminated products, it is evident that the present invention permits free adjustment of the tube winding machine to provide optimum belt pressures at the commencement of any particular tube Winding operation. After the machine is in operation, the desired belt pressure or tension may be easily and simply maintained by adjusting control wheel 43 to correct any variation in the indicator gauge reading. Consequently, little effort is required to produce laminated tubular products of uniform size, strength and apperance.

While in the foregoing specification specific details of the present invention have been set forth for purposes of illustrating an embodiment thereof, it will be apparent to those skilled in the art that many of these details can be varied widely without departing from the spirit and scope of this invention.

We claim:

1. In a tube winding machine having a carriage equipped with spaced roller-supporting assemblies and an endless tube-winding belt extending therebetween, one of said assemblies being movable with respect to the other for varying belt tension, the combination comprising a rotatable and axially movable shaft threadedly connected to the movable assembly and extending in the direction of movement thereof, said shaft being connected to a member hinged upon said carriage for swinging movement in response to axial movement of said shaft, and force-responsive means mounted upon said carriage and operatively engaging said hinged member, said forceresponsive means being provided with indicator means for indicating belt tension translated through the movable assembly and imposed upon the hinged member by said shaft.

2. The structure of claim 1 in which said force-responsive means comprises a U-shaped bar having a pair of deflection legs, one of said legs arranged for receiving a force directed thereagainst by said carriage and the other of said legs arranged for receiving a force directed thereagainst by said hinged member.

3. In an apparatus of the character described for forming spirally wound laminated tubes, a base, a mandrel support mounted upon said base and extending upwardly therefrom, an elongated mandrel carried by said mandrel support, a belt carriage mounted upon said base and being equipped with a pair of spaced apart rollers, one on each side of said mandrel, means for rotating said rollers, an endless belt entrained about said rollers and being looped over said mandrel for guiding laminating strips upon said mandrel in the forming of a spirally wound tube, a roller support structure adjustably carried by said carriage and being movable towards and away from said mandrel, one of said rollers being rotatably supported upon said stucture so that movement of said adjustable roller support structure changes the tension exerted by said belt upon said mandrel, force-responsive means adapted to have a force imposed thereacross and being equipped with force indicator means for registering the magnitude of that force, a member hingedly connected to said carriage and having a free end portion bearing against said force-responsive means, and a shaft connecting said hinge member to said movable roller support structure and extending in the direction of movement of said structure, whereby, belt tension is transmitted by said movable structure, said shaft, and said hinge member to said force-responsive means.

4. The structure of claim 3 in which said shaft is rotatable and is threadedly received by said movable roller support structure for moving said structure in response to rotation of said shaft.

5. In a tube-forming apparatus, an elongated mandrel adapted to have a tube formed thereon, a carriage equipped with a pair of roller support structures, one on each side of said mandrel, one of said roller support structures being fixed with respect to said mandrel and the other being movable toward and away from the mandrel, a pair of rollers each being rotatably supported by one of said roller support structures, an endless belt entrained about said rollers and looped over said mandrel for guiding laminating strips about said mandrel in forming a spirally wound tube, a hinge member pivotally mounted upon said carriage and operatively connected to said movable roller support structure for pivotal movement in response to movement of said structure towards and away from said mandrel, and force-responsive means mounted upon said carriage and operatively engaging said hinge member, said means being responsive to forces imposed upon said hinge member by said movable support structure and relative to said carriage, said means also being provided with indicator means for indicating belt tension translated through said movable support structure and imposed upon said hinge member, a rotatable shaft extending between and operatively connecting said movable roller support structure and said hinge member, said shaft being threaded along one end portion thereof and said movable roller support structure having a threaded opening therein adapted to threadedly receive said shaft, whereby rotation of said shaft causes movement of said roller support structure with reference to said mandrel to selectively increase and decrease the tension of said belt, and self-aligning thrust bearing means carried by said shaft and hinge member for preventing lateral displacement of said shaft as said hinge member pivots in response to changes in belt tension.

References Cited in the file of this patent UNITED STATES PATENTS 1,258,731 Yingling Mar. 12, 1918 1,323,818 Berry Dec. 2, 1919 2,112,252 Sang Mar. 29, 1938 2,311,762 Kottmann Feb. 23, 1943 2,696,109 Bennett Dec. 7, 1954 FOREIGN PATENTS 18,169 Great Britain 1908 

